1. Technical Field
The present invention relates to engines. More specifically, the present invention relates to camless engines and to methods of improving efficiency of engines.
2. Background Art
Internal combustion engines that utilize pistons have been used in automobiles and other motorized devices for many years. Conventional camshafts are used to control the opening of the valves and are driven by a crankshaft. The camshaft is designed to rotate either in the engine block or on the cylinder head to open and close the valves. The camshaft is driven by the crankshaft and the camshaft includes egg-shaped surfaces called cam-lobes to open the valves. The position of the lobe is precise in opening and closing the valves when the shaft rotates. The lobe determines how far the valve opens and the duration it takes to open the valve.
There are several different arrangements of camshafts, such as single overhead cam, double overhead cam, and pushrod. Single overhead cam (SOHC) means that the engine has one cam per head, such as four or six cylinders inline. The double overhead cam (DOHC), such as the V-6 or V-8 engine, has two cams—one for each head. The cam actuates the rocker arms that press down the valves to open the valves. Spring returns the valves to their closed position. At a very high speed, these springs have to be very strong, otherwise the valves might lose contact with the rocker arm. This can result in extra wear and tear on the cams and rocker arms. On the single and double overhead cam engines, the cams are driven by the crankshaft by using a chain (timing chain) or a belt (timing belt). These chains and belts need to be changed regularly as per the engine's maintenance schedule, because if they break, the camshaft stops spinning and the piston will hit the open valve and damage both the piston and the valve as well as other parts. The main reason to use the double overhead cam is to facilitate more air in the cylinder and to expel more exhaust air. The engine thereby gains more power.
In the SOHC and DOHC, valves are located in the head above the cylinder. In a pushrod engine, the camshaft is in the engine block rather than in the head. The long rods add mass to the system, which increases the load on the valve springs. This can limit the speed of the pushrod engine; the overhead camshaft, which eliminates the pushrod from the system, is one of the engine technologies that made higher engine speeds possible. The camshaft in a pushrod engine is often driven by gears or a short chain. Gear-driven camshafts are generally less prone to breaking than belt drives, which are often found in overhead cam engines.
In the typical internal combustion engine, the use of camshafts results in a power loss of the engine of 20%. The conventional design of the internal combustion engine regarding the use of camshafts has not changed in many years. There remains a need for an engine with greater efficiency and a new design of actuating pistons.